(03-20-2017 23:52)davidbrady Wrote:  Some folks like to paint their roofs. Here's an ultra-high reflectance bright white acrylic roof paint which is probably as good as it gets in terms of solar reflectance:

Solar Reflectance:
Method: ASTM C1549,
Initial: .92
Aged: .87

http://www.nationalcoatings.com/acryshield-ultra-high-reflectance-a590

Some folks like Bus Kote, but I can't find a published solar reflectance spec for it.

(03-21-2017 20:40)davidbrady Wrote:  Hi Hish,

I think this paint only reflects solar light and does little to encourage heat transfer.

Here's an interesting research project: http://www.sciencemag.org/news/2017/02/cheap-plastic-film-cools-whatever-it-touches-10-c

These guys created a film composed of glass beads and backed by a silver mirror. The mirror reflects 96% of the sun's energy and the glass beads absorb heat from the body that the film is in contact with, it could be our bus rooftops. The glass beads then resonate and radiate the heat into outer space as infrared energy. According to the article, this film can passively cool any surface by as much as 50 deg F.

(03-21-2017 21:24)Maudi2001 Wrote:  

(03-21-2017 20:40)davidbrady Wrote:  Hi Hish,

I think this paint only reflects solar light and does little to encourage heat transfer.

Here's an interesting research project: http://www.sciencemag.org/news/2017/02/cheap-plastic-film-cools-whatever-it-touches-10-c

These guys created a film composed of glass beads and backed by a silver mirror. The mirror reflects 96% of the sun's energy and the glass beads absorb heat from the body that the film is in contact with, it could be our bus rooftops. The glass beads then resonate and radiate the heat into outer space as infrared energy. According to the article, this film can passively cool any surface by as much as 50 deg F.

The FAA would ban it as too reflective and blind pilots. LOL